Rendell replied, "No, absolutely not. Joe Biden is here to stay. Next vice president of the United States."

However, according to recent polls, Biden's popularity is not as high as Republican vice presidential nominee Sarah Palin. Results from a CNN/Opinion Research Corp. national survey released yesterday have Obama and McCain virtually tied – Obama has 49 percent while McCain has 48 percent. But Sarah Palin has surged ahead of Biden on popularity with 55 percent to his 44 percent. Her favorability rating is also 6 percent higher.

Following Sen. Joe Biden's recent statement that Hillary Clinton might have been a better choice for Obama's running mate, a popular online trading exchange website is taking wagers on whether Biden will be withdrawn from the ticket.

"Make no mistake about this," Biden said at a Nashua, N.H., rally. "Hillary Clinton is as qualified or more qualified than I am to be vice president of the United States of America. Let's get that straight. She's a truly close personal friend, she is qualified to be president of the United States of America, she's easily qualified to be vice president of the United States of America, and quite frankly, it might have been a better pick than me. But she's first rate, I mean that sincerely, she's first rate, so let's get that straight."

"Barack Obama's most important decision of this election, and Biden – the candidate he selects – suggests, himself, that he wasn't the right man for the job, and that Hillary Clinton would have been a better choice. Biden certainly has a credible viewpoint on this."

However, Rendell said he believed Biden was only being "gracious" with his comment about Clinton as a better vice presidential pick.

"Look, I think Joe's been a very good asset to the ticket," he said. "I said all along during this time period after Senator Obama became the presumptive nominee that I thought, electorally Hillary Clinton was our best choice. But Joe's done a very good job."

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Many Clinton supporters pushed for an Obama/Clinton ticket following the primaries, arguing she would help Obama win over Hispanics and blue-collar voters. Rather than vetting Clinton, Obama announced Biden as his running mate two days before the Democratic National Convention. Now some are speculating about what could happen to Obama's quest for the presidency if Biden is dropped from the ticket.

The "Sean Hannity Show" featured a reader poll on its website asking, "If Biden gets yanked, is it over?"

Approximately 6.49 percent said "No, he could win," while 22.08 percent said it depends on other circumstances.